Ignition coil and filter shield assembly



Feb. 22, 1949. E. c. HALLETT 2,462,491

IGNITIQN CQIL AND FILTER SHIELD ASSEMBLY Filed Oct. 22, 1945 2Sheets-Sheet 1 FIG. 1

mmvrm Ellen QHzHelZ BY Patented Feb. 22, 1949 IGNITION COIL AND FILTERSHIELD I ASSEMBLY Elton C. Hallctt, Inglewood, Calii., assignor toHallett Manufacturing Company, Inglewood, Calif., a corporation ofCalifornia I Application October 22, 1945, Serial No. 623,774 4 Claims.(Cl. 123-148) My invention relates to the shielding and protection ofelectric units comprising portions of the ignition system of combustionengines and has particular reference to a metallic housing whichcompletely encloses certain of the units, as for example, an ignitioncoil and electric filter, so that the units are protected againstmoisture and other outside influences while being at the same timeshielded so that any high frequency electric radiations generated inthem will be prevented from passing outwardly in such a way as tointerfere with reception in a radio receiving set which may be mountedin the immediate vicinity.

Under particular circumstances radio equipped vehicles may be used insuch a way that there is danger of water, moisture, dust and the likecollecting around the engine parts sufliciently to damage the parts andparticularly units of the ignition system. In order to assure continuedoperation of the engine the ignition units which might be thus damagedmust be protected. Moreover, in order to maintain a compactness in thedesign of the engine as a whole, it is found advantageous to incorporateelectric shielding for the same ignition system units in some mannerwith the Weather protecting features.

It is therefore among the objects of my invention to provide a new andimproved housing for combustion engine ignition units which is compactin design and which performs a double function of shielding the unitfrom possible damage due to water, moisture, dust and the like andshielding or isolating the units with respect to electric radiations sothat operation of the units will not interfere with operation of a radioset carried by the vehicle.

Another object of my invention is to so construct a shielding housing ina special manner so that compartments within the housing are shieldedfrom each other electrically in order that radiations set up in theunits of one compartment do not magnify radiations present in one of theother units.

Still another object is to subdivide individual compartments in ahousing so that radiations emanating from a connection at one end of anelectric unit are shielded from the other end of the same unit.

A further object of my invention is to construct a shielding housing ina new and improved manner so that supports within the housing forelectric units are compactly, economically and efficiently designed inorder that the units may be properly spaced within suitablecompartments,

securely anchored in place, and at the same time properly grounded forelectric shielding purposes.

With these and other objects in view, my invention consists in theconstruction, arrangement and combination of the various parts of mydevice whereby the objects contemplated are attained, as hereinaftermore fully set forth, pointed out in my claims and illustrated in theaccompanying drawings. in which:

Fig. 1 is a top view of the device with the lid partially broken away toreveal the interior.

Fig. 2 is a longitudinal sectional view taken on the line 2-2 of Fig. 1.

Fig. 3 is a cross sectional view taken on the line 33 of Fig. 1.

Methods have been known in the radio'art whereby metal shielding isutilized on electric conductors in and around radio circuits in order toprevent the radio circuits from picking up interfering high frequencyelectric radiations and it may Well be that shielding of this sort hasbeen used on portions of the ignition system of combustion engines.Where engines are designed to permit their use under conditions wherethey may be regularly operated in the presence of water, moisture, dustand dirt more careful at tention must be given to the protection ofelectric units against the action of weather. To date however, there hasnot been devised a satisfactory compact protection for such electricunits which insures their continued and successful performance under allconditions and which likewise shields them sufliciently so that whenevera vehicle operated by the engine carries radio equipment there will beno interference with radio transmission whether the vehicle is at rest,running at idling speed, or being operated over a rugged countryside.

In an embodiment of my invention chosen for the purpose of illustrationI have shown a housing comprising what may be designated as a box [0 ofmetallic material or other strong and rigid material having the capacityof conducting electricity on which are provided extensions H providedwith apertures l2 by means of which the box may be bolted or otherwisefastened to some portion of a. combustion engine. The box as illustratedhas relatively high walls so that the compartments therein are deep andis provided with a lid I3 having a flange I4 around its perimeter facedwith a gasket l5 which is adapted to be pressed into sealingrelationship with the top edges 16 of the box walls. Machine screws 11pass through bosses I 4 at the corners of the lid, through corner bulgesin the gasket and thence 3 into threaded engagement l8, etc., of the boxso that down tightly against the top edges of the box in order to makethe interior of the box waterproof, moisture proof and dust proof. Thecorner bulges of the gasket prevent any leak around the screws. On thewalls of the box are provided fittings 22, 23 and 24 to which tubing maybe secured in order that electric leads may enter the housing through awaterproof conduit.

Within the box there is provided an interior partition wall 25 which isintegral with the bottom and side walls. The partition separates theinterior into two parts comprisingta larger compartment 26 and a smallercompartment 21. In the partition is an aperture 28 having an insulatedlining 29 forming a passage between the compartments. On the lid is aninterior rib 30 which coincides with the top edge of the partition whenthe lid is in closed position making a continuous separating wallbetween the two compartments. By this device one compartment iselectrically shielded from the other.

Within the compartment 26 there are provided saddles 3i and 32 disposedparallel to each other and spaced from the end walls of the compartment.It will be noted that the saddles are relatively narrow and are integralwith the bottom and side walls of the compartment. Each of the saddleshas a recessed central portion 33 adapted to receive an ignition coil34. The coil is bound to the saddle in each case by means of a strap 35preferably metallic which is anchored to the top edge of the saddle oneach side of the recessed central portion by means of screws 36. Mountedin this manner the ignition coil is spaced from the bottom, side walls,end walls and lid of the compartment. By the arrangement shown the coilis securely anchored in its proper position so that the spacing at oneend may be proper in view of the configuration of one end of the coil. Abay 3! is provided in one end wall so that the central portion of thebay is spaced from the extreme end of the coil 34.

In the compartment 21 is an electric filter coil which is designed torest upon a laterally extending fiat topped boss 4|. The filter coil isheld in place by means of a specially designed bracket 42 whichencompasses the top, sides and ends of the filter and has feet 43anchored to bosses 44 at the bottom by means of screws 45.

Compartment 2'! is subdivided so that-one terminal 48 which may be a hotwire terminal is shielded electrically from another terminal 49 at theopposite end which may be a cold wire terminal. The shielding isaccomplished by a pair of vertical ribs 50 and 5! at the sides of thefilter which extend upwardly from the ends of the boss 4| and a rib 52extending from the top of one vertical rib to the top of the other butwhich is formed on the inside of the lid. It will be noted that althoughthe ribs need not actually touch the outside of the filter, they arenevertheless'of such a height that there is only a small space betweenthe edge of the rib in each case and the with corner bosses I8, I

the lid may be pulled adjacent surface of either the filter or thebracket which surrounds the filter. In keeping with the desirability ofbringing the ribs close to the surface of the filter the vertical ribsare shown cut out as at 53 so that the lower portion hugs the surface ofthe filter and the upper portion hugs a portion of the bracket which.overlies the side of the filter. A connection 54 electrically connectsthe terminal 49 of the filter with a terminal 55 of the ignition coil.The connection passes through the lining 29 of the aperture 28 leavinglittle or no space in order to preserve as nearly as possible a completeelectric shield between the two compartments J, Both electric units,being provided with casings of electrically conductin materials, aregrounded with their respective mountings to the box and hence to thecombustion engine.

By the arrangement shown there has been provided a compact housing forelectric ignition units which completely encompasses the unitsindividually with a weather-proof electric shielding protection sodesigned and applied that not only is each unit isolated from the otherand from the exterior but also so that terminals of different potentialon opposite ends of the same unit are shielded from each other.

Having described my invention, what I claim,

as new and desire to secure by Letters Patent is:

1. An internally shielded housing for electric units comprising: a boxof electrically conducting material having a compartment for thereception of one said unit, a lid therefor sealed at the edges andincluding an electrically continuous mechanical connection from the lidto the body, means for supporting the unit in spaced relation to thesurrounding walls of the compartment and ribs extending from the wallsinwardly to positions adjacent the unit, said ribs lying in a laterallyintersecting plane intermediate the ends of the unit whereby thecompartment is divided into subcompartments electrically shielded onefrom another.

2. In an internally shielded housing for electric units of a combustionengine ignition systom the combination of a plurality of electric unitcasings, a box of electrically conducting material having a compartmentfor the reception of one said casing, a lid for the box sealed at theedges and including an electrically continuous mechanical connectionfrom the lid to the box, a bracket partially surrounding the casing andanchored to the box for supporting the casing in spaced relation to thesurrounding walls of the compartment and ribs extending from the wallsinwardly to positions adjacent the casin and the bracket, said ribslying intermediate the ends of the casing, certain of said ribs beingcut out to fit around said bracket, said bracket and casing jointly withsaid ribs comprising a partition dividing the compartment intosubcompartments electrically shielded one from another. Y

3. In an internally shielded housing for electric units of a combustionengine ignition system the combination of an ignition coil casing, afilter casing and a box having an internal partition dividing theinterior into a compartment for reception of said ignition coil casingand a compartment for reception of said filter coil casing adapted forinclusion of a filter having hot and cold wire terminals at therespective ends thereof, and a lid for the box, one said compartmenthaving a boss of electrically conducting material on the bottomintermediate the ends extending from side wall to side wall forsupporting the filter, vertical ribs of electrically conducting materialon the side walls in the same plane as the boss extending inwardly tothe filter, and a transverse rib forming part of the lid spanning thedistance between the tops of the vertical ribs and extending inwardly tothe filter, said ribs jointly with the filter comprising a partition inthe smaller compartment between two sub-compartments, one adjacent eachterminal, substantially shielded electrically from each other and fromthe larger compartment.

' 5 t a 4. An internally shielded housing for an elec- REFERENCES CITEDtric unit comprising a box of electrically conduct- The followingreferences are of record in the ing material forming a compartment, anelectric file of this patent:

umt 1n the compartment having oppositely disposed hot and cold wireterminals, and ribs ex- UNITED STATES PATENTS tending transverselyinwardly in the same plane a Number Name Date from the Walls of thecompartment to the unit 1 157 592 Seeley Oct 19 1915 forming spacersbetween said unit and the com- 1353116 Lingle Sept 1920 partmeut wallsand said ribs jointly with the unit 1949846 Slotsky 1934 comprising apartition separating said compart- 10 2088454 whisk "July 1937 ment intosubcompartments housing the respec- 2:114189 fi QZILL Apt 1938 tive hotand cold wire terminals. 2,163,843 Lansing et a1 June 27, 1939 2 2 8 4ELTON C- H ALLETT. 0855 Appleton July 23 19 0 2,388,054 Hartzell d. Oct.30, 1945

